2.2 Circulatory System Flashcards
What is the role of Red blood cells ?
Carry oxygen around the body
What is the structure and function of red blood cells ?
- They have a biconcave (disc) shape that provides a large surface area for the diffusion of oxygen
- They contain haemoglobin which is rich in iron, that carries the oxygen
- Have no nucleus and therefore more space for haemoglobin
What is the structure and function of white blood cells (Phagocytes) ?
- Defence against bacteria
- Engulf and digest pathogens
- Larger than red blood cells and fewer in number
- It has a lobed nucleus
What is the structure of white blood cells ( Lymphocytes) ?
- Defence against disease
- Produce antibodies
- Have a large nucleus
- Larger than red blood cells and fewer in number
What is the structure and function of platelets ?
- Very small cell fragments
- Involved in blood clotting and formation of scabs
- Platelets convert the protein molecules to amino acids
- The fibrin forms a mesh network that traps other blood components
What are the main 2 functions of the circulatory system?
- Transport of substances
- Protection against disease
What is the blood composed of and in what amounts
55% liquid plasma and 45% cells
What are the 5 main components of Blood ?
- Red blood cells
- White blood cells (Phagocytes)
- White blood cells (Lymphocytes)
- Platelets and plasma
What is the function of red blood cells?
- carry oxygen around the body
- contain haemoglobin, rich in iron , that carries oxygen
- have a disc (biconcave) shape that provides a large surface area for diffusion of oxygen
- no nucleus, therefore more space for haemoglobin
What shape are red blood cells and why ?
They have a disc/ biconcave shape that provides a large surface area for the diffusion of oxygen
What is the function of Phagocytes (white blood cells) ?
- Defend against bacteria
- Engulf and digest pathogens
- bigger than red blood cells and fewer in number
- Lobed nucleus
What blood cells have a lobed nucleus?
White blood cells (Phagocytes)
What is the function of Lymphocytes ( white blood cells)
- defence against disease
- produce antibodies
- large nucleus
- larger than red blood cells but fewer in number
What is the structure of Lymphocytes
- large nucleus
-larger than red blood cells but fewer in number
What is the structure of red blood cells
- no nucleus therefore more space for haemoglobin
- disc/biconcave shape that provides a large surface area for diffusion of oxygen
- contain haemoglobin rich in iron that carries the oxygen
What is the structure of Phagocytes?
- lobed nucleus
- Larger than red blood cells but fewer in number
- Engulf and digest pathogens
What is the structure and function of platelets
- very small fragments
- involved in blood clotting and formation of scabs
- convert the protein molecules to amino acids
- The fibrin forms mesh network that traps other blood components
What is the structure of platelets?
Very small fragments
What is the function of platelets ?
- Blood clotting and formation of scabs
- Convert the proteins to amino acids
- the fibrin forms a mesh network that traps other blood components
What do platelets do with protein?
Platelets convert the protein molecules to amino acids
What is the structure and function of plasma?
- it is the liquid part of the blood
- responsible for transport of blood cells, glucose, amino acids, CO², hormones and urea
What is plasma responsible for?
The transport of:
- the blood cells
- glucose
- amino acids
- CO²
- hormones
- urea
What is the structure of plasma?
It is the liquid part of the blood
What happens to red blood cells when placed in water?
- They take in water by osmosis and burst in a process called cell lysis or haemolysis.
- This occurs because the concentration of dissolved materials in the plasma is not stable compared to the surrounding water.
- They take in water by osmosis and burst in a process called cell lysis or haemolysis.
- This occurs because the concentration of dissolved materials in the plasma is not stable compared to the surrounding water.
Define the process that occurs when red blood cells burst in water
- Cell lysis or haemolysis
- This is linked to change in os
What type of solution causes red blood cells to swell and burst?
- Hypotonic solution
- Distilled water is an example of a hypotonic solution
What must be kept at a similar concentration in the plasma of the blood and why ?
- The concentration of dissolved materials in the plasma must be kept stable and at a similar concentration to the blood cells
- This is important because if red blood cells are placed in water they will take in water by osmosis and burst in a process called cell lysis or haemolysis
What is the effect of a hypertonic solution on red blood cells?
Cells shrink and shrivel
-This occurs when cells are placed in a concentrated salt solution
Fill in the blank: The process of red blood cells taking in water by osmosis is called _______.
Haemolysis
What type of solution causes red blood cells to shrink and shrivel?
- Hypertonic solution
- Concentrated salt solution is an example of a Hypertonic solution
What equipment is used to view human blood cells on a prepared blood smear?
- A light microscope
- Focus using the low power objective lens before changing it to the higher power objective lens
- It is necessary to adjust the iris diagram to restrict the light passing through the blood smear so as to view the blood cells which are small in size and faint in colour.
Why is it necessary to adjust the iris diagram when viewing human blood cells on a prepared blood smear ?
It is necessary to adjust the iris diagram to restrict the light passing through the blood smear so as to view the blood cells which are small in size and faint colour
How should the blood smear be prepared?
The blood should be smeared across the slide using the edge of a cover slip at a 30-45° angle